Effects of roof angle, inlet gap size and dryer height on temperature and relative humidity in a chimney-dependent solar crop dryer

A chimney dependent solar crop dryer (CDSCD) was developed and studied. Design of Experiment (DOE) employed using statistical three level non randomized factorial experimental design in Minitab software version 19.0. The study effects roof angle, inlet gap size height on temperature revealed that the at which drying tray is positioned (A) (C) influences highest difference, 30.4 °C. It concluded high when small (range area to exit ratio 1.8128:1 1.0877:1) maximum tray’s position 2.18. Optimal values for achieving difference response greater than or equal 32.6 °C are minimum 84 cm, outlet 1.0877:1 angle 81°. effect parameters relative humidity combined (AB) attained standardized 6.6. optimal low (when loaded with 1 kg cassava) were 64°, 2.5379:1 time 19 hours. This could serve as effective tool comparing different designs CDSCD dryers optimum performances be used subsequently refine design.